Less than two years after the Drug Enforcement Administration that “heroin is clearly more dangerous than marijuana,” new Attorney General Jeff Sessions revisited that comparison in remarks today before law enforcement officials in Richmond:

I reject the idea that America will be a better place if marijuana is sold in every corner store. And I am astonished to hear people suggest that we can solve our heroin crisis by legalizing marijuana — so people can trade one life-wrecking dependency for another that’s only slightly less awful. Our nation needs to say clearly once again that using drugs will destroy your life.

Sessions remarks are contradicted by a wealth of medical and policy research.

For starters, researchers and policymakers aren’t suggesting that marijuana legalization will “solve” the heroin crisis. As I noted late last month, there is, however, abundant, peer-reviewed evidence suggesting that legalizing medical marijuana has led to decreases in opioid overdose and mortality rates in a number of states.

Sessions: ‘We don’t need to be legalizing marijuana’

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Expressing his views on drug policy, Attorney General Jeff Sessions said marijuana legalization wouldn’t be “good for us.” He also doubted reports of marijuana’s effectiveness fighting opioid addiction, adding “we need to crack down more on heroin.” (Reuters)

That speaks to Sessions’s second point: that marijuana dependency is “only slightly less awful” than heroin addiction. Drug dependency of any kind is, indeed, awful. And marijuana dependency is quite real.

Second, the federal government’s own research undermines any equivalency between dependency on marijuana and heroin. You can often gauge how bad a given drug addiction is by looking at what happens when a user tries to kick the habit. For heroin, the National Institute on Drug Abuse lists withdrawal symptoms including “muscle and bone pain, sleep problems, diarrhea and vomiting, cold flashes with goose bumps, uncontrollable leg movements severe heroin cravings.”

Finally, researchers have generally ranked marijuana use as far less harmful to individuals and society than heroin use. In a 2010 Lancet report, dozens of researchers and public health experts rated the harm potential of a variety of drugs on a 0 to 100 scale, with 100 being the most harmful. Heroin scored in the mid-50s. Marijuana was rated at a 20.

Sessions’s remarks are “a sort of starting gun for a new war on drugs,” according to Michael Collins of the Drug Policy Alliance, a group working to reform drug laws. “It’s very disappointing that this DOJ and this attorney general are so anti-science and anti-evidence and anti-facts.”

How marijuana legalization in Washington, Colorado and Oregon is working out so far

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Voters in California, Maine, Massachusetts and Nevada just approved recreational marijuana use. Here’s what they can learn from Washington, Colorado and Oregon, states where marijuana use has already been legalized. (Daron Taylor, Danielle Kunitz/The Washington Post)